What Is an Ideal Weight Calculator?
An ideal weight calculator estimates a reasonable target body weight based on your height and sex, using several well-known medical formulas developed for estimating dosages and clinical reference points — plus a BMI-based healthy weight range for comparison.
How to Use the Ideal Weight Calculator
- Select your sex.
- Enter your height in feet and inches.
- Compare estimates from four classic formulas, plus the BMI-based healthy range.
Ideal Weight Formulas (Men)
Ideal Weight Formulas (Women)
The Robinson and Miller formulas use similar structures with slightly different base weights and per-inch increments. All four were originally developed for medical dosage calculations, not as strict weight targets — they're best used as a general reference point alongside the BMI-based range.
Worked Example
Inches over 5 ft: 8
Hamwi: 106 + (6 × 8) = 154 lb
Devine: 50 kg + (2.3 × 8) = 68.4 kg ≈ 151 lb
The formulas typically land within a few pounds of each other for the same height.
Understanding Your Results
Each formula gives a single-point estimate; the Average Estimate blends all four for a general reference. The BMI-Based Healthy Range gives a broader, more flexible range (18.5–24.9 BMI) that many clinicians consider more practical than a single "ideal" number, since healthy weight varies by body composition, frame size, and muscle mass.
Limitations of Ideal Weight Formulas
- None of these formulas account for muscle mass, bone density, or body frame size.
- They were designed decades ago for clinical dosing reference, not as personal weight-loss targets.
- Individual health is influenced by many factors beyond a single weight number — body composition, fitness level, and overall habits all matter.
Frequently Asked Questions
This calculator uses four classic medical formulas (Hamwi, Devine, Robinson, Miller) originally developed for estimating body weight for medication dosing, alongside the BMI healthy weight range.
None is definitively "best" — they typically land within a few pounds of each other and are all population averages rather than personalized targets, so the BMI range is often a more flexible reference.
No — none of these formulas distinguish muscle from fat, so muscular individuals may have a healthy weight well above the calculated estimate.
Treat it as a general reference point rather than a strict target — body composition, frame size, and overall health matter more than hitting an exact number.
Yes — the formulas use different base weights and per-inch increments for men and women, reflecting average differences in body composition.